More people with dementia need to be treated in the community and allowed to die at home, an expert has claimed.

The number of people with the condition is expected to double in the next 20 years, according to Dr Peter Passmore, professor of ageing and geriatric medicine at Queen's University Belfast.

Dr Passmore also said that Alzheimer's disease sufferers in Northern Ireland survive less than six years on average once they are diagnosed.

Dementia is a disorder associated with an ongoing decline of the brain and includes Alzheimer's.

Dr Passmore said: "They need to stay in the community throughout the course of their illness. They need to be able to die with dignity, if they can, within their homes.

"There has to be a recognition that at the moment this is a palliative condition. Expectations are that people live forever."

Dementia is an umbrella term used to refer to a collection of symptoms that can result from a number of different diseases of the brain.

Those symptoms include a decline in memory, reasoning and communication skills and a gradual inability to carry out everyday activities.

There are many different types of dementia but they all affect how the brain works and have a massive impact on quality of life.

Dr Passmore addressed guests at Stormont at the launch of Belfast Central Mission's (BCM) plans to build Copelands, a state-of-the-art dementia and nursing care home in Millisle, Co Down, that will create 60 jobs.

Dr Passmore said there needed to be more centres like it as rates of diagnosis improved and warned that too many nursing-home patients, one out of three with dementia, were being treated with anti-psychotic drugs.

About 19,000 people are living with the condition but that figure is expected to rise sharply as people live longer.

The average survival rate for people diagnosed with Alzheimer's is 5.9 years, according to Dr Passmore. Northern Ireland has one of the highest diagnosis rates of dementia in the UK.

Around 40 per cent of people in hospital have the condition and are admitted for related problems like falling or pneumonia. They tend to spend longer in hospital, costing the health system dearly.

Dr Passmore said if care was to shift to the community, then options needed to be available.

He said t he overall level of population awareness in Northern Ireland was huge and patients were being treated sooner - a lady aged just 54 was diagnosed with dementia recently.

The doctor witnessed the "intellectual disintegration" of patients at his Belfast City Hospital clinic from when they were first diagnosed with dementia and their personality was still apparent.

"This is an awful disease and it has a worse prognosis than some cancers," he added.

"It is the most feared diagnosis of all, if you have cancer you remain with your mental faculties."

He added people had up to 20 years cut off life expectancy. "That is a tragic figure."

He said there were no medical specialism in treating dementia patients in nursing homes, monitoring is delegated to GPs.

"This is no respector of class or creed. It is equally devastating wherever you come from," he added.

Health Minister Edwin Poots said the expected increases in numbers of people with dementia produced further pressures on health and social care services.

"My Department's policy direction is about promoting health and wellbeing, social inclusion and services to support the independence of older people," he said.

"I am committed to ensuring that people with dementia are treated with awareness and respect.

"The voluntary and independent sector, including organisations such as the Belfast Central Mission, are vital in supporting my department as we continue in our efforts to promote independent living."